Swivel-joint for electric currents.



PATENTED JULY 2l, 1908.

A. E. SMITH. SWIVEL JOINT EOE ELECTRIC GUEEENTS.

APPLICATION FILED MAR. 22, 1906. RBNEWBD MAY 1.1907.

, one of the poles of the circuit.

-acter capable of being connected with any material, as ber,

-base 2.

threaded AUGUSTUS B. SMITH, OF WILKINSBURG, PENNSYLVANIA. v

SWIVEL-JOINT FOR ELECTRIC CURRENTS.

Specification of Letters Patent.

Patented July 21, 1908.

Application filed. March 22, 1906, Serial No. 307,515. Renewed. May 1, 1907. Serial No. 371,240.`

To all whom it may concern.'

Be it known that I, AUGUSTUS B. SMITH, a' citizen of the United States, residing at Wilkinsburg, in the county ofA Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Swivel,- Joints for Electric Currents, of which the following is a specification, reference being had therein to the accompanying drawing.

My invention refers to improvements in swivel joints for electric conductors, and has for its object to provide a device of this charstationary source of current, as a socket and provided with a depending rotatable portion with which the current distributing wires are connected, by which the ultimate current consuming device, as a movable motor or any other equivalent may be freely moved around in various directions, without interru tion of the current circulation.

eferring now to the drawings zFigure 1. is a view of the device in elevation, the connecting socket being shown in dotted lines. Fig. 2. is a central vertical section of Fig. 1. Fig. 3. is a perspective detail view of one of the upper pair of ball race contacts. Fig. 4. is a similar view ofv the lower rotating ball race contact. Fig. 5. is a horizontal sectional view on the line V. V. of Fig. 2.@ Fig. 6. is a similar section on the line VI. VI. of Fig. 2. Fig. 7. is a similarsection on the line VII. VII. of Fig. 2. Fig. 8. is a. detail view of the centralstem.

The device generally consists of astationary base 2 and a rotating base 3 of insulating said base 3 being rotatably connected with relation to the stationary The base 2 is provided with an upper outer threaded thimble 4 or other suitable contact adapted to be screwed into or otherwise connected with a receiving current supplying base A, shown in dotted lines, with the inner shell of which the screw threaded base or socket 4 makes electrical contact for 5 is a stationary stem screw threaded throughout its middle portion as shown, abutting at its upper end against the central contact portion of base socket A, with which it makes electrical contact and constitutes (the other vpole of the circuit. The base 2 surrounds and is mounted upon stem' -5 and is fixedly secured therein by means of the portion enga in a corres ondinfl'` threaded cgutrgalhole iind is tseri-7 interiorly by means of curely held by means of a locking nut 6 and its washer, as clearly shown. The upper por- -tion of the threaded shell or thimble 4 is the center `of the rotating block 3 and is pro-l vided with a terminal dlsk 8 at the bottom, which supports the lower block and its connections, while the adjacent ends of blocks 2 and 3 are provided with current transmittin rin s 9 and 10 having oppositely disposed bal race grooves arranged to receive the circular series of bearing balls 11 of steel or other suitable current-transmitting material. The lower rotatin block 3 is also provided with a similar bal race bearing 12 between which and the stationary supporting disk 8 of stem 5 are arran ed an annular series of similar bearin ba ls 13, and by. this construction it wil be seen that the free rotation of the block 3 is greatly facilitated.

By adjusting the stem '5, the blocks 2 and 3 may be vaccurately set with relation to each other and rigidly maintained by reason of the threaded engagement with the upper block and lock nut 6. Depending downwardly from the lower lportion of block 3 is a terminal coping shell 14 secured to block 3'by screws 15 or otherwise, into the interior of which arel introduced the terminals 16, 17, of the current distributing wires b. The end of wire 17 is electrically connected with ball race 12 by means f binding screw nuts 18 making contact through threaded stem 19 and lateral lug 2O of ring 12, by which construction a current is at all times established through stem 5 to wire 17 from the center contact vof base A. Wire 16 is connected by binding screw nut 2l with stern or wire 22 extending downwardly from the rotating ball race'ringlO, in constant electrical circuit with the upper stationary ball race 9, which ball race ring 9 is connected -with the other contact of base A a connecting wire 23 connected with threaded shell 4, or by other suitable current conveying device. Y

24 is a disk of insulating material extending across the bottom of rotating block 3, thereby effectually insulating the disk 8 from accidental contact with either of wires 16 or 17.

By this construction and arrangement it will be seen that both poles of the current are at all times maintained in circuit with distributing 4wires 16, 17 irrespective ofwhatbio . as for instance in making it in ever position the current consuming device to which these wires lead, may assume. The wires may be moved around in any direction or may be twisted and the lower rotatable base will freely move around by reason of the intervening rolling connections which also serve to transmit the current at all times.

In place of the balls 11 or 13, it will be understood that rollers of any form may be employed, or wheels or other equivalent devices adapted to facilitate the turningoperation and at the same time to transmit the current from the stationary circuit terminals to 'the rotating terminals, to functionsin view.

It will be understood that the arrangement or design of the device may be reatly varied, isk form with much greater diameter and less height, or

that various other changes or variations may be made by the skilled mechanic but all such changes are to be considered as within the scopehof the following claims.

at I claim is 1. A swivel joint for electric currents comprising a stationary base provided with current supplying terminals, a rotatable portion provide with current consuming terminals, and intervening unattached rolling current transmitting devices, substantially as set forth.

2. vA swivel joint for electric currents comprising a stationary base provided with current sup lying' terminals, a rotatable portion provide y with current consuming terminals, and separate series of unattached rolling current transmittin devices arranged to establish communication between the stationary and the rotating terminals respectively, substantiallyas set forth. y

perform the 3. A swivel joint for electric currents comprising a stationary base provided with an outer contacting shell, and an inner contacting stem having current transmitting terminals, 'a rotatable portion provided with current consuming terminals, and movable current transmitting devices intervening between the stationary base and the rotatable portion adapted to maintain electrical com` munication between said contacting shell and stem and said current 'consuming terminals, substantially as set forth.

4. A swivel joint forelectric currents comprising a stationary base provided with an outer contacting shell, a ball race ring, and

an inner contacting stem secured in the stationary base and provided with an abutting contact and terminal flange; and a rotatable portion having a corres onding ball race rin and a series of contact alls, a secondary ba race rin and a series of balls engaging the termina flange, and current consuming wires connected with the rings of the rotatable portion, substantiall as set forth.

5. In a swivel joint` or electric currents,

the combination of a stationary base having a central stem provided with an abutting terminal and a terminal flange, an exterior contacting shell and a communicating ball race ring, a rotatable portion provided with a primary ball race ring and a series of balls communicating with the ring of the shell, a secondary ball race ring and a series of balls communicating with the terminal flange, and` means for connecting current consumin wires with the primary and secondary bail racerings respectively, substantially as set forth.

6. In a swivel joint for electric currents, the combination of a stationary base having a central stem provided with an abutting terminal and a terminal flange, an exterior contacting shell and a communicating ball race ring, a rotatable portion provided with a primary ball race ring and' a series, of balls a central stem provided with an' abutting terminal and a terminal flange, an exterior contacting shell and a communicatin ball race ring, a rotatable portion provide with a primary ball race ring and a series of balls communicating with the ring of the shell, a seconda ball race ring and a series of balls communicating with the Aterminal flange, and v means for connecting current consuming wires with the primary and secondary bal race rings respectively, with a transverseiiisulating disk mounted between the central stem and the contacting shell, substantially `as set forth.

8. In a swivel joint for electric currents, the combination of a stationary base having a central stem providedwith an abutting terminal and a terminal flange, an exterior contacting-shell and a communicatin ball race ring, a rotatable portion provide with a primary ball race ring and a series'of balls communicating with the ring of the shell, a secondary ball race ring and a series of balls communicating with the terminal flange,l

and means for connecting current consumin Wires with the primary andv secondary ba race rings res 'ectively, with a transverse insulating diap agm coverin the ,terminal iiange, and a .transverse insulating disk mounted between the central stem and the contacting shell, substantiall asset forth.

9A In a swivel joint for e ectric currents,

the combination with a base portion having."

current-supplying elements, of a relatively rotatable portion having current conveyingA ses-,seo

elements, and intervening unattached rolling current-transmitting devices.

10. In a swivel joint for electric currents, the combinationwith a base portion having means for making electrical connection with a source of supply, a relatively rotatable element having means for distributing the current, and intervening unattached rolling devices arranged to make electrical communication between the base portion and saidrotatable element.

11. A swivel joint for electric currents comprising a base portion having a currentsupplying element and constitutin a raceway, a relatively movable portion aving a` current-conveying element and constituting a companion race-way, and intervening current-transmitting devices in rolling contact with each of said race-way portions.

12. A swivel joint for electric currents comprising a grooved base portion having a current-transmittin element and constituting a raceway, a re atively movable portion having a current-transmitting element'and constituting a companion race-Way, and intervening current-transmitting devices in rolling contact with each of said race-way portions.

18. In a swivel 'oint for electric currents, the combination with a base portion having a current-supplying element, of a relatively rotatable portion having a current-conveying ,element, and intervenin contact balls. j 14. In a swivel joint Ior electric currents, the combination with a base portion having a current-supplying. element, of a relatively rotatable portion having a current-conveying element, and intervening rolling currenttransmitting devices relatively movable with relation to each of said ortions.

In testimony whereofp I aHiX my signature in presence of two witnesses.y

AUGUSTUS B. SMITH.` Witnesses CHAs. S. LEPLEY, C. M. CLARKE. 

